6:30 AM | *The “Carrington Event” of 1859…this ferocious solar storm of 165 years ago may not be as rare as once thought…what it could mean in today’s world*
Paul Dorian
The Carrington Event was caused by a powerful coronal mass ejection (CME). (Image credit: NASA/Goddard Space Flight Center)
Overview
On September 1st, 1859, a ferocious solar storm took place that impacted much of the planet. This ferocious solar storm is now known as the “Carrington Event”, named after the British astronomer, Richard Carrington, who witnessed the largest solar flare from his own private observatory which caused a major coronal mass ejection (CME) to travel directly toward Earth. Recent studies of solar storms have warned that these type of “Carrington Events” may not be quite as rare as once thought (e.g., Hayakawa et al). Many previous studies leaned heavily on Western Hemisphere accounts, omitting data from the Eastern Hemisphere. A super storm of the same magnitude as the “Carrington Event” in today’s world would very likely have a much more damaging impact than it did in the 19th century potentially causing widespread power outages along with disruptions to navigation, air travel, banking, and all forms of digital communication.
Discussion
The sun has been very active this year as Solar Cycle 25 progresses towards a solar maximum which is anticipated to take place sometime during 2025. In fact, there has not been a single day in 2024 (or 2023) without sunspots which can be compared to 281 such days in 2019…the time of the last solar minimum. Solar Cycle 25 has turned out to be stronger than its predecessor with more sunspot activity than solar cycle 24 which featured the fewest number of sunspots since Solar Cycle 14 back in the early 1900’s. Even weak solar cycles, however, can produce significant solar storms. In fact, the “Carrington Event” of 1859 took place during a weak solar cycle (#10).
Illustrated plate based on observations by the British astronomer Richard Christopher Carrington (1826-1875), showing a group of sunspots, taken from 'Memoirs of the Royal Astronomical Society', 1861. On 1st September 1859, in the course of these observations, he noticed two areas in the middle of a sunspot group grow rapidly brighter (points A and B in the sketch), before dimming and disappearing at points C and D. This was the first recorded observation of a solar flare.(Courtesy SSPL / Getty Images)
The solar storm of September 1, 1859
Coming just a few months before the solar maximum of 1860, numerous sunspots began to appear on the surface of the sun on 28 August 1859 and were being observed in different parts of the world. Just before noon on the cloudless morning of Thursday, September 1, 1859, 33-year-old astronomer Richard Carrington - widely acknowledged at the time to be England’s best - was in his own private observatory and, as he usually did on sunny days, he used his telescope to project an 11-inch wide image of the sun on a screen and carefully drew the sunspots that he saw. Suddenly, two brilliant beads of blinding white light appeared over the sunspots, intensified rapidly, and became kidney-shaped. He realized that he was witnessing something unprecedented and left for about one minute to find another witness. On returning within 60 seconds, he and his witness found that much had already subsided in that short time.
Circled areas on plot indicate locations that experienced the northern lights (auroras) during the “Carrington Event” of 1859
The next morning, Friday, September 2nd, 1859, when the CME arrived, it crashed into Earth's magnetic field, causing the global bubble of magnetism that surrounds our planet to shake and quiver. The CME reached the Earth some 17.6 hours after the eruption which is much quicker than the normal journey time of 3 or 4 days as an earlier CME actually cleared the way of the ambient solar plasma for the second blast to move so quickly. Rapidly moving fields induced enormous electric currents that surged through telegraph lines and disrupted communications. In fact, telegraph systems all over Europe and North America went haywire and, in some cases, telegraph operators were literally shocked as sparks were flying and telegraph paper was often set on fire. Some systems actually continued to work despite being disconnected from their power supplies as aurora-induced electric currents still allowed messages to be transmitted. Skies all over Earth erupted in red, green and purple auroras - even in tropical locations like Cuba, Jamaica, El Salvador, the Bahamas and Hawaii. The auroras were so bright over the Rocky Mountains that their glow awoke gold miners who began preparing breakfast because they thought it was morning. People in the northeastern US could read a newspaper by the aurora’s light.
On Saturday, September 3, 1859, the Baltimore American and Commercial Advertiser reported, "Those who happened to be out late on Thursday night had an opportunity of witnessing another magnificent display of the auroral lights. The phenomenon was very similar to the display on Sunday night, though at times the light was, if possible, more brilliant, and the prismatic hues more varied and gorgeous. The light appeared to cover the whole firmament, apparently like a luminous cloud, through which the stars of the larger magnitude indistinctly shone. The light was greater than that of the moon at its full, but had an indescribable softness and delicacy that seemed to envelop everything upon which it rested. Between 12 and 1 o'clock, when the display was at its full brilliancy, the quiet streets of the city resting under this strange light, presented a beautiful as well as singular appearance.”
Sunspot drawings by German astronomer Heinrich Schwabe on 27 August 1859 (left), 1 September 1859 (center), and close‐up figure of 1 September 1859 (right), reproduced from RAS MS Schwabe 31 (p. 131 and p. 136; Image courtesy of the Royal Astronomical Society, Hayakawa et al. Circles in the upper halves correspond to the solar disk, on which the sunspots are drawn with the numbers.
Back in the 19th century there were no X-ray satellites or radio telescopes and no one knew solar flares existed until that September morning. "What Carrington saw was a white-light solar flare—a magnetic explosion on the sun," explains David Hathaway, solar physics team lead at NASA's Marshall Space Flight Center in Huntsville, Alabama. "It's rare that one can actually see the brightening of the solar surface," says Hathaway. "It takes a lot of energy to heat up the surface of the sun!" The explosion witnessed by Carrington produced not only a surge of visible light, but also a mammoth cloud of charged particles and detached magnetic loops—a "CME"—and hurled that cloud directly toward Earth.
“Carrington Event” - not as rare as once thought
Most experts today regard the “Carrington Event” of 1859 as one of the most powerful geomagnetic storms in recorded history. However, new findings suggest that it may be something that occurs more frequently than previously thought and perhaps more of an imminent threat to modern society. A good example is the great storm of mid-September 1770, when extremely bright red auroras blanketed Japan and parts of China. Captain Cook himself saw the display from near Timor Island, south of Indonesia. Hayakawa and colleagues recently found drawings of the instigating sunspot, and it is twice the size of the Carrington sunspot group — paintings, dairy entries, and other newfound records, especially from China, depict some of the lowest-latitude auroras ever, spread over a period of 9 days. “We conclude that the 1770 magnetic storm was comparable to the Carrington Event, at least in terms of auroral visibility,” wrote Hayakawa and colleagues in a 2017 Astrophysical Journal Letter. Moreover, “the duration of the storm activity was much longer than usual.”
An eyewitness sketch of red auroras over Japan in mid-September 1770. [Ref]
Hayakawa’s team has delved into the history of other storms as well, examining Japanese diaries, Chinese and Korean government records, archives of the Russian Central Observatory, and logbooks from ships at sea–all helping to form a more complete picture of events. They found that superstorms in Feb 1872 and May 1921 were also comparable to the “Carrington Event”, with similar magnetic amplitudes and widespread auroras.
Oriental reports of a giant naked-eye sunspot group (left) and auroras (right) in Feb. 1872. [Ref]
Impact of a “Carrington-type” event on today’s world
Today we know that solar flares happen frequently, especially during solar sunspot maximums. In today’s world, electronic technologies have become embedded into everyday life and are, of course, quite vulnerable to solar activity. Power lines, long-distance telephone cables, radar, cell phones, GPS, and satellites – all could be significantly affected by an event like this one. In other words, the world’s high-tech infrastructure could grind to a halt disrupting daily activities from purchasing a gallon gas to using the Internet.
Of particular concern is the fear about what this kind of solar storm could do to the electrical grid since power surges caused by solar particles can blow out giant transformers. If numerous transformers happened to be destroyed at once, it would likely take a painfully long time to replace them. The eastern US is especially vulnerable since the power infrastructure is highly interconnected so that failures in one location could cause failures in other regions. One long-term solution to this vulnerability would be to rebuild the aging power grid to be less susceptible to solar disruptions.
Final thoughts
On the positive side, there is comfort in the fact that observations of the sun in today’s world are a constant with a fleet of spacecraft in position to monitor the sun and gather data on solar flares. Also, there is better forecasting today and solar scientists could give some sort of warning as to when solar flares might appear and whether a given storm is pointed at Earth. Improved forecasting can allow for mitigating actions to be taken since the most damaging emissions travel slowly enough to be detected by satellites well before the particles strike the Earth. For example, power companies could protect valuable transformers by taking them offline before a solar storm strikes. One thing is certain, we should be prepared for another massive solar storm of the magnitude of the “Carrington Event” of 1859 as new information suggests these have likely been occurring much more often than previously thought.
Meteorologist Paul Dorian
Arcfield
arcfieldweather.com